BRUSSELS--Electronics giants Philips Electronics NV, Samsung SDI Co. Ltd. (006400.SE) and Panasonic Corp. (PC) are among a group of seven companies fined 1.47 billion euros ($ billion) by European regulators Wednesday for operating a two-decade-long cartel in TV and computer monitor tubes.

The European Commission said LG Electronics Inc. (066570.SE), Philips Electronics NV and Samsung SDI participated in both cartels, while Panasonic, Toshiba Corp. (6502.TO), MTPD--a Panasonic subsidiary--and Technicolor--formerly Thomson--participated only in the cartel for television tubes.

Whistle-blower Chunghwa from Taiwan has received full immunity from fines as it was the first company to reveal the cartels' existence. Other companies received reductions of their fines for cooperating in the probe.

"These cartels for cathode ray tubes are "textbook cartels': they feature all the worst kinds of anticompetitive behavior that are strictly forbidden to companies doing business in Europe," Joaquin Almunia, European Union antitrust chief, said.

The Commission said the two cartels were among the "most organized cartels' that it had investigated.

Write to Vanessa Mock at vanessa.mock@dowjones.com

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